Apple’s foray into digital textbooks for iPad is obviously geared toward students; however, having Apple’s hand in the textbook market may increase the appeal of some titles to readers who aren’t purchasing the book for a class. Hopefully the textbook section of iBooks, which is woefully bare at present, will swell with titles that readers will buy just for their own edification.

If it sounds crazy to say that there’s no need to be a student or an academic to purchase textbooks from the App Store, think twice, because it has already happened.

Inkling’s runaway hit, The Professional Chef ($49.99) showed that iPad owners are willing to shell out the cash for an app that promises to give them specialized knowledge regardless of student status. Certainly The Professional Chef is an exception in the digital textbook world, but Apple’s new textbook initiative leaves plenty of room for new, and profitable, exceptions.

Inkling also sells its books by the chapter, which only increases the chance that a curious soul will try a sample of The Professional Chef since the cost of a chapter is only $2.99 compared to the fifty bucks one has to lay out to buy all 36 chapters at once.

If a high-end cookbook could sell, then surely textbooks written to appeal to other areas, particularly part-time passions with a steep learning curve, have the potential to succeed. Most hobbyist subcultures have their own instructional bibles. For example, the legendary knitter’s guide Principles of Knitting by June Hemmons Hiatt, is finally coming back into print. After decades of paying in excess of $200 for a copy on eBay, knitters can finally own a copy of the original text for less than $40. But imagine for a moment that in addition to the Nook and Kindle versions, it was also available as a dedicated textbook for iPad. If Principles of Knitting (or POK, as it’s known in knitting circles) came with the type of enhancements described in Apple’s initiative, the iPad version of the book would be a must-own for any dedicated knitter.

Principles of Knitting isn’t technically a textbook, but that’s only because knitting isn’t on most educational curricula. Expand the idea to subjects that are both hobbies and educational subjects (photography, drawing, fashion design, landscape design), and it’s easy to imagine that high quality text books for a particular area could cross over to non-students and sell extremely well. For example,a Music Appreciation textbook might have the potential for wide appeal, particularly if it came with built-in audio and video.

The long arm of the App Store further increases the chance that Apple’s initiative will spawn another cross over hit like The Professional Chef. It’s even possible that new classics may spring from the hopefully creative (albeit) closed system that Apple is creating, and the line between textbook and authoritative book app will continue to blur.

Apple’s ability to ferret out the best aspects of other technologies will help grow the market, as will user’s desire to have the highest quality information available. Buyers will be more likely to know about text books with cross over potential because they will be available in the App Store rather than being relegated to college book stores across the country.

Practical details such as the ability to highlight text, the lower cost and lack of a physical footprint will benefit students and non-students alike. A textbook’s ability to be updated through iTunes helps ensure that a user’s investment in a lifelong love will not molder on a shelf after a few years.

But most importantly, users can curate their own digital libraries, tailored to their specific interests. General reference books as well as titles that broadly cover medicine, writing, basic web design could all find homes on the iPads of many non-student users.

Users will not be able to resist the opportunity to hone and customize their digital libraries, filling their iPads with textbooks that reflect their own particular skill set or avocation. Much like choosing just the right case, lock screen, or stylus, purchasing a library of apps and digital books to use over the long haul taps into many users’ desire to kit out their iPads in a way that is personal and meaningful.

Regardless of whether Apple’s textbook initiative revolutionizes learning at the secondary level, it is bound to have an effect on those who already appreciate the immersive experience that educational apps for the iPad already offer.

One key to the iPad’s popularity is its ability to so many things well. It enriches the lives of those users who take advantage of all of the educational apps and books that are already available.

Sure, the offerings in the App Store today are rather sparse, with nothing as alluring as some of Inkling’s offerings. But it wouldn’t surprise me if Apple is planning to take a page out of Inkling’s virtual book, and hopefully it will lead to the development of irresistible, informative textbooks that will appeal to anyone interested in lifelong learning, whether or not they have a student id.